1. Field of the Invention
The invention relates to locks.
2. Brief Description of the Prior Art
A known lock comprises a body, a locking member moveable relative to the body between locked and unlocked positions and a locking mechanism operable to lock the locking member in the locked position and release the locking member for movement to the unlocked position. It is known to incorporate in such locks electrical equipment such as, for example, an alarm that operates when an attempt is made to tamper with the lock. The alarm is usually housed separately in the body together with a power source and it may be accessed through an access door for maintenance and battery replacement. This requires the lock to be adapted to accept the electrical equipment and also requires tools to remove and replace it. Each lock must be adapted separately to contain the electronics.
According to the invention, there is provided a lock comprising a body, a locking member movable relative to the body into and away from a locked position, a mechanical locking unit engaged with the body and lockable to lock the locking member in the locked position and unlockable to release the locking member for movement away from said locked position, a cavity leading into the body and a sub-unit located in the cavity, the sub-unit including a power source and a system powered by the source, the locking unit closing said cavity when engaged with the body and, when said locking member is unlocked, being disengageable from the body.
The sub-unit can be accessed following disengagement of the locking unit. By including the power source and powered system in the sub-unit, these can be accessed for maintenance and replacement and/or operation.
The following is a more detailed description of two embodiments of the invention, by way of example, reference being made to the accompanying drawings in which: